how do I access the photos in my 32 bit iPhoto software and convert to 64 bit Photo (apple software)?

Close the photos app

Hold down the option key and open photos

When prompted, select the iPhoto library you wish to convert

You may wish to keep a backup of the original library (just in case) but I've never had issues

Keeping the original iPhoto Library for some time is very useful for two reasons:

• Photos may not have been able to migrate all photos, and we may notice only later, if photos are missing from the original library.
• The iPhoto library may be the only place where or original image files are stored unmodified. After the Catalina upgrade we need an archive of our original image files, because Photos 5 on Catalina is renaming all original files and we are no longer able to find them in the library package by their original names. If we are ever in a situation that Photos can no longer open the library, it will be very difficult to find our photos, as the original image numbers are gone.